U.S. patent application number 14/209469 was filed with the patent office on 2015-09-17 for wellhead hanger with spacer to reduce break-out torque.
The applicant listed for this patent is CAMERON INTERNATIONAL CORPORATION. Invention is credited to Dennis P. Nguyen, Jay P. Painter.
Application Number | 20150260002 14/209469 |
Document ID | / |
Family ID | 54068387 |
Filed Date | 2015-09-17 |
United States Patent
Application |
20150260002 |
Kind Code |
A1 |
Nguyen; Dennis P. ; et
al. |
September 17, 2015 |
WELLHEAD HANGER WITH SPACER TO REDUCE BREAK-OUT TORQUE
Abstract
A wellhead hanger assembly is provided. In one embodiment, a
system includes a wellhead hanger, such as a casing hanger. This
system also includes a spacer ring positioned along a neck of the
wellhead hanger between a threaded portion of the neck and a
shoulder of the wellhead hanger. In at least some instances, the
spacer ring may cooperate with a running tool threaded onto the
wellhead hanger to reduce the break-out torque needed for
disconnecting the running tool from the wellhead hanger. Additional
systems, devices, and methods are also disclosed.
Inventors: |
Nguyen; Dennis P.;
(Pearland, TX) ; Painter; Jay P.; (Friendswood,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CAMERON INTERNATIONAL CORPORATION |
HOUSTON |
TX |
US |
|
|
Family ID: |
54068387 |
Appl. No.: |
14/209469 |
Filed: |
March 13, 2014 |
Current U.S.
Class: |
166/382 ;
166/77.52 |
Current CPC
Class: |
E21B 43/10 20130101;
E21B 33/0415 20130101 |
International
Class: |
E21B 33/04 20060101
E21B033/04; E21B 43/10 20060101 E21B043/10 |
Claims
1. A system comprising: a wellhead hanger; and a spacer ring
positioned along a neck of the wellhead hanger between a threaded
portion of the neck and a shoulder of the wellhead hanger, wherein
the spacer ring is threaded onto an additional threaded portion of
the neck, and wherein the threaded portion and the additional
threaded portion are threaded in opposite directions.
2. The system of claim 1, comprising a running tool.
3. The system of claim 2, wherein the running tool is threaded onto
the neck of the wellhead hanger via the threaded portion such that
the spacer ring is positioned between the running tool and the
shoulder and prevents the running tool from bottoming out against
the shoulder.
4. (canceled)
5. (canceled)
6. A system comprising: a wellhead hanger; and a spacer ring
positioned along a neck of the wellhead hanger between a threaded
portion of the neck and a shoulder of the wellhead hanger, wherein
the spacer ring is threaded onto an additional threaded portion of
the neck, and wherein the threaded portion includes a right-handed
thread and the additional threaded portion includes a left-handed
thread.
7. The system of claim 1, wherein the shoulder is a landing
shoulder of the wellhead hanger.
8. The system of claim 1, comprising a hollow wellhead body,
wherein the wellhead hanger and the spacer ring are installed
within the hollow wellhead body.
9. The system of claim 1, wherein the wellhead hanger is a casing
hanger.
10. The system of claim 1, comprising a spring positioned between
the spacer ring and the shoulder such that the spring applies a
biasing force against the spacer ring.
11-15. (canceled)
16. A method comprising: attaching a spacer to a wellhead hanger;
threading a running tool onto the wellhead hanger by rotating the
running tool in a first direction with respect to the wellhead
hanger to thread the running tool onto the wellhead hanger; and
drawing the running tool and the spacer into engagement along the
wellhead hanger; wherein attaching the spacer to the wellhead
hanger includes threading the spacer onto the wellhead hanger by
rotating the spacer with respect to the wellhead hanger in a second
direction, opposite the first direction, to thread the spacer onto
the wellhead hanger.
17. The method of claim 16, comprising lowering a casing string
attached to the wellhead hanger into a well.
18. A method comprising: attaching a spacer to a wellhead hanger;
threading a running tool onto the wellhead hanger by rotating the
running tool in a first direction with respect to the wellhead
hanger to thread the running tool onto the wellhead hanger; drawing
the running tool and the spacer into engagement along the wellhead
hanger; lowering a casing string attached to the wellhead hanger
into a well; and rotating the casing string in the first direction
via the wellhead hanger and the running tool, wherein the
engagement of the running tool with the spacer causes rotation of
the running tool to be applied to the wellhead hanger and the
spacer reduces torque needed to unthread the running tool from the
wellhead hanger.
19. (canceled)
20. The method of claim 16, comprising positioning a spring between
the spacer and a shoulder of the wellhead hanger.
Description
BACKGROUND
[0001] This section is intended to introduce the reader to various
aspects of art that may be related to various aspects of the
presently described embodiments. This discussion is believed to be
helpful in providing the reader with background information to
facilitate a better understanding of the various aspects of the
present embodiments. Accordingly, it should be understood that
these statements are to be read in this light, and not as
admissions of prior art.
[0002] In order to meet consumer and industrial demand for natural
resources, companies often invest significant amounts of time and
money in finding and extracting oil, natural gas, and other
subterranean resources from the earth. Particularly, once a desired
subterranean resource such as oil or natural gas is discovered,
drilling and production systems are often employed to access and
extract the resource. These systems may be located onshore or
offshore depending on the location of a desired resource. Further,
such systems generally include a wellhead assembly mounted on a
well through which the resource is accessed or extracted. These
wellhead assemblies may include a wide variety of components, such
as various casings, valves, hangers, pumps, fluid conduits, and the
like, that facilitate drilling or production operations.
[0003] As will be appreciated, various tubular strings can be run
into wells through wellhead assemblies. For instance, wells are
often lined with casing that generally serves to stabilize the well
and to isolate fluids within the wellbore from certain formations
penetrated by the well (e.g., to prevent contamination of
freshwater reservoirs). Such casing is frequently cemented into
place within the well. During a cement job, cement can be pumped
down a casing string in a well, out the bottom of the casing
string, and then up the annular space surrounding the casing
string. The cement is then allowed to set in the annular space.
Wells can also include tubing strings that facilitate flow of
fluids through the wells. Hangers can be attached to the casing and
tubing strings and received within wellheads to enable these
tubular strings to be suspended in the wells from the hangers.
SUMMARY
[0004] Certain aspects of some embodiments disclosed herein are set
forth below. It should be understood that these aspects are
presented merely to provide the reader with a brief summary of
certain forms the invention might take and that these aspects are
not intended to limit the scope of the invention. Indeed, the
invention may encompass a variety of aspects that may not be set
forth below.
[0005] Embodiments of the present disclosure generally relate to
hangers for suspending tubular strings from wellheads. In some
instances, these wellhead hangers can be attached to the tubular
strings and installed in a wellhead assembly with running tools
threaded onto the hangers. Once a wellhead hanger is installed in
the wellhead, the running tool can be unthreaded from the hanger.
In certain embodiments, a wellhead hanger includes a spacer that
facilitates disconnection of the running tool from the hanger. In
one embodiment, the wellhead hanger includes left-handed and
right-handed threaded portions for engaging mating threads of the
spacer and the running tool. The spacer, the running tool, and the
wellhead hanger cooperate with one another to inhibit over-torquing
of the running tool onto the hanger and to reduce the break-out
torque needed to begin unthreading the running tool from the
hanger.
[0006] Various refinements of the features noted above may exist in
relation to various aspects of the present embodiments. Further
features may also be incorporated in these various aspects as well.
These refinements and additional features may exist individually or
in any combination. For instance, various features discussed below
in relation to one or more of the illustrated embodiments may be
incorporated into any of the above-described aspects of the present
disclosure alone or in any combination. Again, the brief summary
presented above is intended only to familiarize the reader with
certain aspects and contexts of some embodiments without limitation
to the claimed subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] These and other features, aspects, and advantages of certain
embodiments will become better understood when the following
detailed description is read with reference to the accompanying
drawings in which like characters represent like parts throughout
the drawings, wherein:
[0008] FIG. 1 generally depicts various components, including one
or more tubular strings and associated hangers, that can be
installed at a well in accordance with one embodiment of the
present disclosure;
[0009] FIG. 2 is a cross-section of a wellhead assembly including a
casing hanger, with a spacer and a running tool threaded onto the
casing hanger, in accordance with one embodiment;
[0010] FIG. 3 is a detail view of the spacer and portions of the
casing hanger and running tool of FIG. 2;
[0011] FIGS. 4 and 5 depict an example of mating threads of the
spacer, the casing hanger, and the running tool of FIGS. 2 and 3 in
accordance with one embodiment; and
[0012] FIG. 6 depicts a spring-loaded spacer installed on a casing
hanger of a wellhead assembly in accordance with one
embodiment.
DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS
[0013] Specific embodiments of the present disclosure are described
below. In an effort to provide a concise description of these
embodiments, all features of an actual implementation may not be
described in the specification. It should be appreciated that in
the development of any such actual implementation, as in any
engineering or design project, numerous implementation-specific
decisions must be made to achieve the developers' specific goals,
such as compliance with system-related and business-related
constraints, which may vary from one implementation to another.
Moreover, it should be appreciated that such a development effort
might be complex and time consuming, but would nevertheless be a
routine undertaking of design, fabrication, and manufacture for
those of ordinary skill having the benefit of this disclosure.
[0014] When introducing elements of various embodiments, the
articles "a," "an," "the," and "said" are intended to mean that
there are one or more of the elements. The terms "comprising,"
"including," and "having" are intended to be inclusive and mean
that there may be additional elements other than the listed
elements. Moreover, any use of "top," "bottom," "above," "below,"
other directional terms, and variations of these terms is made for
convenience, but does not require any particular orientation of the
components.
[0015] Turning now to the present figures, a system 10 is
illustrated in FIG. 1 in accordance with one embodiment. Notably,
the system 10 is a production system that facilitates extraction of
a resource, such as oil, from a reservoir 12 through a well 14.
Wellhead equipment 16 is installed on the well 14. As depicted, the
wellhead equipment 16 includes at least one casing head 18 and
tubing head 20, as well as wellhead hangers 22. But the components
of the wellhead equipment 16 can differ between applications, and
could include a variety of casing heads, tubing heads, spools,
hangers, sealing assemblies, stuffing boxes, pumping tees, and
pressure gauges, to name only a few possibilities.
[0016] The wellhead hangers 22 can be positioned on landing
shoulders 24 within hollow wellhead bodies (e.g., within the tubing
and casing heads). These landing shoulders 24 can be integral parts
of tubing and casing heads or can be provided by other components,
such as sealing assemblies or landing rings disposed in the tubing
and casing heads. Each of the hangers 22 can be connected to a
tubular string, such as a tubing string 26 or a casing string 28,
to suspend the string within the well 14. The well 14 can include a
single casing string 28 or include multiple casing strings 28 of
different diameters. Casing strings 28 are often cemented in place
within the well. During a cement job, cement is typically pumped
down the casing string. A plug is then pumped down the casing
string with a displacement fluid (e.g., drilling mud) to cause the
cement to flow out of the bottom of the casing string and up the
annular space around the casing string.
[0017] Rotating a casing string during cementing can increase
uniformity of the cement about the casing string and reduce the
size or frequency of undesirable cavities or fissures in the
cement. Further, rotating tubular strings can also facilitate
running of the strings into the well through the wellhead. Any
suitable devices or machines may be used to rotate the wellhead
hangers (and their attached tubular strings) and to run the strings
into wells. For example, a top drive can be used to run a casing
string into a well and to rotate the casing string. In some
instances, the tubular strings are rotated via wellhead hangers
attached to the strings.
[0018] One example of a wellhead assembly 30 having a hanger
installed in a hollow wellhead body is depicted in FIG. 2. As shown
in this figure, the hanger is provided as a mandrel-type casing
hanger 32 installed in a casing head 34. The casing hanger 32
includes a shoulder 36 that is landed onto a mating landing
shoulder 38 of the casing head 34. While the shoulders 36 and 38
are depicted as integral shoulders of the casing hanger 32 and
casing head 34, the shoulders could be provided separately in other
embodiments. Although not shown in the present figure, it will be
appreciated that the shoulder 36 can include flow-by recesses that
allow fluid to flow through the shoulder 36 when the casing hanger
32 is installed in a wellhead.
[0019] A casing string 40 is attached to the casing hanger 32 by
way of a threaded interface 42. This allows the casing string 40 to
be lowered into a well 14 through the wellhead assembly 30 via the
casing hanger 32. The casing string 40 can be run through other
casing strings of greater diameter within the well, such as through
a wider casing string attached to a casing hanger 44 also within
the wellhead.
[0020] A running tool 48 is used to run the casing hanger 32 into
the casing head 34. In FIG. 2, the casing hanger 32 has a neck 50
above the shoulder 36. The running tool 48 is threaded onto a
threaded portion 52 of the neck 50, and a landing joint 54 is
attached to the running tool 48 via a threaded interface 56. The
landing joint 54 and the running tool 48 may be operated to lower
the casing hanger 32 into the wellhead and the casing string 40
into the well. In some embodiments, the casing string 40 and the
casing hanger 32 may be lowered through an additional wellhead
component 58, such as through a blowout preventer stack, connected
to the casing head 34. The landing joint 54 can be used to rotate
the running tool 48, the casing hanger 32, and the casing string
40, such as during cementing of the casing string 40 within the
well.
[0021] The wellhead assembly 30 also includes a spacer 60 attached
to the casing hanger 32 between the running tool 48 and the
shoulder 36. In at least some embodiments, including that depicted
in FIG. 2, the spacer 60 is provided in the form of a spacer ring
threaded onto a threaded portion 62 of the neck 50. This threaded
portion 62 is on the neck 50 between the threaded portion 52 and
the shoulder 36.
[0022] A detail view of the spacer 60 and the running tool 48
attached to the casing hanger 32 is provided in FIG. 3. As shown
here, the shoulder 36 of the casing hanger 32 includes a tapered
surface 68, which engages the shoulder 38 of the casing head 34,
and an opposite surface 70. In at least some embodiments, the
spacer 60 is threaded onto the threaded portion 62 and prevents the
running tool 48 from bottoming out against surface 70 of the
shoulder 36 as the running tool 48 is threaded onto the threaded
portion 52 above the spacer 60. As used herein, "threaded onto"
refers to relative rotation of two components to engage a threaded
connection between the components and does not require a particular
one of those components to be driven in rotation. For instance, the
spacer 60 being threaded onto the threaded portion 62 includes
rotating the spacer 60 with respect to a stationary threaded
portion 62 of the neck 50, rotating the threaded portion 62 with
respect to a stationary spacer 60, or rotating both the threaded
portion 62 and the neck 50 with respect to one another.
[0023] The threaded portions 52 and 62 of the casing hanger 32 may
have different diameters. For instance, as shown in FIG. 3, the
threaded portion 62 of the neck 50 has a wider outer diameter than
that of the threaded portion 52, with this difference resulting in
a lateral surface 72. The spacer 60 can prevent the running tool 48
from bottoming out against this surface 72, as well.
[0024] As shown in FIGS. 4 and 5, the running tool 48 and the
spacer 60 can be drawn into engagement (e.g., such that end
surfaces 74 and 76 of these components contact one another) along
the neck 50 of the casing hanger 32. In some embodiments, the
spacer 60 is threaded onto the portion 62 of the neck 50 and the
running tool 48 is then threaded onto the portion 52 so that the
running tool 48 translates along the neck 50 and engages the spacer
60. The spacer 60 can then be turned to increase a compressive
force from the spacer 60 on the running tool 48. In other
embodiments, the spacer 60 is threaded onto the portion 62, the
running tool 48 is threaded onto the portion 52 but positioned
apart from the spacer 60, and the spacer 60 is then turned on the
portion 62 to translate the spacer 60 along the neck 50 into
engagement with the running tool 48.
[0025] An example of mating threads of the casing hanger 32, the
running tool 48, and the spacer 60 are also depicted in FIGS. 4 and
5. As shown in these two figures, the threaded portion 52 of the
casing hanger 32 includes a thread 78 that engages a thread 80 of
the running tool 48, and the threaded portion 62 of the casing
hanger 32 includes a thread 86 that engages a thread 88 of the
spacer 60. The threads 78, 80, 86, and 88 could be provided in any
suitable manner. For instance, these threads could each be provided
as a single helical thread with a trapezoidal form (e.g., an Acme
thread). In other embodiments, however, these threads could be
provided as multi-start threads, with different thread forms, and
so forth. Mating engagement of the running tool 48 with the casing
hanger 32 via threads 78 and 80 enables the casing hanger 32 to be
rotated by with the running tool 48 (e.g., when driven by a top
drive via the landing joint 54). This, in turn, allows the casing
string 40 to be rotated by the casing hanger 32, such as during
cementing of the casing string 40 within the well.
[0026] The running tool 48 could be used without the spacer 60 to
transmit torque to the casing hanger 32 and drive rotation of the
casing string 40. Resistance to such rotation (e.g., from the
weight of the casing string 40 or cement in the well) could cause
tightening of the connection between the running tool 48 and the
casing hanger 32. In some instances, such tightening would lead to
over-torquing of the running tool 48 on the casing hanger 32, in
which excessive friction between these two components would hinder
disengagement of the running tool 48 from the casing hanger 32.
That is, the tightening of the connection between these components
can increase the break-out torque needed to overcome the friction
in the connection and disengage the running tool 48 from the casing
hanger 32, thus frustrating removal of the running tool 48 from the
casing hanger 32 once it is installed within the casing head 34. If
the break-out torque were excessively high, the casing hanger 32
could simply rotate with the running tool 48 when trying to
unthread the running tool 48 from the neck 50, for example. But in
accordance with the present techniques, the spacer 60 can be used
to reduce the break-out torque needed to break the connection
between the running tool 48 and the casing hanger 32.
[0027] In at least some embodiments, the surfaces of the threaded
portions 52 and 62 are threaded in opposite directions to
facilitate disconnection of the running tool 48 from the casing
hanger 32. In certain embodiments, for example, the mating threads
78 and 80 include right-handed threads and the mating threads 86
and 88 include left-handed threads. The spacer 60 can be threaded
onto the casing hanger 32 by rotating the spacer 60 in one
direction (e.g., counter-clockwise in the case of mating
left-handed threads 86 and 88) with respect to the casing hanger 32
to engage the mating threads 86 and 88 and to translate the spacer
60 along the neck 50 of the casing hanger 32 toward the shoulder
36. The running tool 48 can then be threaded onto the casing hanger
32 by rotating the running tool 48 in an opposite direction (e.g.,
clockwise in the case of mating right-handed threads 78 and 80)
with respect to the casing hanger 32 to translate the rotating tool
48 along the neck 50 toward the spacer 60. The spacer 60 and the
running tool 48 can be drawn into engagement with one another in
any suitable manner, such as described above.
[0028] The landing joint 54 can then be rotated in the same
direction as the direction in which running tool 48 was threaded
onto the casing hanger 32 (e.g., clockwise) to drive rotation of
the running tool 48, the casing hanger 32, and the attached casing
string 40 in that direction. As noted above, such rotation can
facilitate cementing of the casing string 40 within the well. As
the running tool 48, the casing hanger 32, and the casing string 40
are rotated by the landing joint 54, the different orientations of
the threads 78 and 80 compared to threads 86 and 88 will cause the
running tool 48 to press against the spacer 60 (axially downward
along the neck 50 in FIGS. 2-5) and the spacer 60 to press against
the running tool 48 (axially upward along the neck in FIGS. 2-5).
This mating engagement of the running tool 48 with the spacer 60
inhibits further axial travel of the running tool 48 down along the
neck 50, allowing the running tool 48 to transmit torque and rotate
the casing hanger 32. Additionally, the mating engagement of the
running tool 48 and the spacer 60 also reduces the break-out torque
necessary to begin backing the running tool 48 off of the casing
hanger 32, allowing the running tool 48 to be more easily
unthreaded from the threaded portion 52 and removed from the
wellhead assembly 30.
[0029] The spacer 60 could also be spring-biased in certain
embodiments. In one embodiment generally depicted in FIG. 6, for
example, a spring 94 is positioned between the spacer 60 and the
shoulder 36 of the casing hanger 32. The spring 94 can include a
disc spring or any other suitable spring to apply a biasing force
on the spacer 60 toward the running tool 48. In the depicted
embodiment, the threaded portions 52 and 62 can be threaded in
opposite directions as described above. The spring 94 and the
spacer 60 balance axial loading from the running tool 48 as it
presses against the spacer 60 while driving rotation (e.g., in the
clockwise direction) of the casing hanger 32 and the casing string
40. The spring 94 may assist the unloading of the running tool 48
against the spacer 60 when the running tool 48 is rotated in the
opposite direction (e.g., counter-clockwise), thus facilitating
disconnection and removal of the running tool 48 from the casing
hanger 32.
[0030] Additionally, although certain embodiments are described
above as having a casing hanger 32 including a spacer 60 for
reducing the break-out torque needed for disconnecting a running
tool 48 from the casing hanger, other embodiments may take
different forms. For example, in some embodiments the hanger 32
could instead be provided as a tubing hanger for installation in a
tubing head. Additionally, while the hanger 32 can be used to
rotate an attached tubular string (e.g., during cementing
operations), the hanger 32 might not be used for this purpose in
other instances.
[0031] While the aspects of the present disclosure may be
susceptible to various modifications and alternative forms,
specific embodiments have been shown by way of example in the
drawings and have been described in detail herein. But it should be
understood that the invention is not intended to be limited to the
particular forms disclosed. Rather, the invention is to cover all
modifications, equivalents, and alternatives falling within the
spirit and scope of the invention as defined by the following
appended claims.
* * * * *